Electronic circuit structure with optimized space requirement according to available volume

ABSTRACT

To make optimum use of an available volume exhibiting in particular surfaces of small radius of curvature, with a view to housing electronic circuits therein, a stack ( 11 ) of layers of possibly different compositions (circuits, components, insulants, etc.) is made, these layers being parallel to the surface of largest dimension of this volume.

BACKGROUND OF THE INVENTION

The present invention relates to a structure of electronic circuitshaving optimized bulk as a function of the volume available.

FIELD OF THE INVENTION

When aircraft, in particular combat aircraft, are required to carrybulky electronic equipment, and when the room available is limited, andespecially when this equipment requires a clear “view” for exampletowards the front of the aircraft, this equipment is placed in the noseof the carrier, in the base of the fin, in the wings or in “pods”(special containers) fixed under the craft. The shape of these locationswhere the equipment can be housed is often very jagged and/or theirdimensions are small, thereby preventing utilization of the entirevolume available, owing to the fact that this equipment is generallyenclosed in packages of simple geometrical shapes, which cannot bematched to the said jagged shapes.

SUMMARY OF THE INVENTION

The subject of the present invention is a structure of electroniccircuits whose external shape can easily be matched in an optimal mannerto virtually any shape of housing intended to receive this equipment,this being achieved without disturbing the operation of the equipment,whose components may be as diverse as possible, whilst having optimalperformance.

The structure in accordance with the invention comprises at least onestack of layers comprising at least one of the following elements:electrical circuits, electronic circuits, optical circuits, waveguides,discrete components, integrated components, protector elements, thermalelements, insulation elements, stiffening elements; these layers beingsubstantially parallel to the largest surfaces of the volume available,in particular substantially plane surfaces, or at the very least themost plane surfaces of the volume available. Advantageously, at leastone of the lateral surfaces of the structure optimally hugs the leastplane shape of the volume available. Thus, by virtue of the invention,the said elements can occupy a volume of arbitrary shapes, includingshapes having small radius of curvature.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood on reading the detaileddescription of several embodiments, taken by way of non-limitingexamples and illustrated by the appended drawing in which:

FIG. 1 is a simplified sectional view of a volume having a profile withsmall radius of curvature, in which the known structures make itpossible to house only antennas, without their circuits (phase shifters,power supply etc.), leaving a non-negligible volume unoccupied,

FIG. 2 is a simplified sectional view of a volume in which the inventionmakes it possible to place antennas, with their circuits, it beingpossible to orient these antennas in very different directions,

FIGS. 3 to 5 are respectively a simplified exploded perspective view andsectional views along IV—IV and V—V of FIG. 3, these figures referringto an exemplary embodiment of a structure in accordance with theinvention, and

FIG. 6 is a simplified sectional view of a volume in which a structureaccording to the invention is placed, this view showing only thelocations of two antennas directed in orthogonal directions, togetherwith the plungers relating to these two antennas, these plungers formingpart of one and the same layer of the multi-layer structure of theinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The invention is described hereinbelow with reference to a structure ofantennas and of associated circuits for equipment such as electronicwarfare equipment, airborne radar equipment and telecommunicationshardware, but it is of course not limited to these applications alone,and can be implemented so as to produce structures incorporating variousmechanical and/or electrical and/or electronic and/or optical and/orthermal elements, in particular to allow these elements to be housed involumes which hitherto were deemed to be too small and/or to have shapeswhich were too “tortuous” to allow the optimal housing therein ofelements which were traditionally placed in packages, generally ofparallelepipedal shape, leaving too much unoccupied volume.

The volume portion 1 represented in FIG. 1 is for example the anteriorpart of the leading edge of the wing 2 of a fighter aircraft. Generally,nothing is housed in this anterior part. This portion has, in section,an approximately “U”-shaped form, the curved part of which is directedtowards the front of the aircraft. This curved part has a small radiusof curvature and is therefore housed with great difficulty. Its internalvolume 3 is unoccupied, being as it is too small to make it possible tohouse therein the packages of the circuits located upstream of theantenna (phase shifters, power supply, etc.). These packages have aparallelepipedal general shape, even the smallest dimension of which isgreater than the distance D separating the branches of the “U”.

Diagrammatically represented in FIG. 2 is a volume portion 4, similar tothe portion 1 of FIG. 1, in which the invention makes it possible tohouse not only antennas 5 directed towards the front of the carrieraircraft, but also antennas 6 directed towards the ground, as well ascircuits, referenced 7 as a whole, incorporated in an integrated mannerwith the antennas, in stratified form, as explained hereinbelow.According to the invention, the planes of the strata are parallel to thelargest surfaces of the volume available, in particular to the planesurfaces, such as the surfaces 8 of the volume portion 4. As a result,the frontal parts 9 of the strata hug the frontal shape 10 of the volumeportion 4 as faithfully as possible, the latter having one (or several)small radius (radii) of curvature.

Represented in more detail in FIGS. 3 to 5 is a simplified exemplarystratified structure 11, similar to the structure 7. This structure 11comprises a stack of layers whose contents, thickness and nature may bevery diverse.

Certain layers of the structure 11, such as the layers 12 may be layersmade of an insulating material or of a material which absorbs shocks andvibrations. These layers 12 are, for example, the outer layers of thestructure, as well as intermediate layers which provide mutualinsulation between the layers 13 comprising uninsulated conductingelements. Elements may be included or formed within several successivelayers 14. These elements are, for example, integrated antennas. To thisend, the layers 14 comprise cutouts directly forming the horns 15, 16 ofthe antennas (or any other type of antenna), integrated into thestructure 11. The horns such as the horn 15 have their axis directedparallel to the planes of the strata, whereas the axis of the horns suchas the horn 16 is perpendicular to these planes of the strata. Ofcourse, the axes of other horns could be oblique with respect to theplanes of the strata.

Other layers comprise simple and/or complex electronic circuits. Thus,for example, the layers 17 comprise the plungers 18 for exciting theantenna horns 15 and 16 and the links between these plungers and thecircuits which are just upstream (in general phase shifters, whendealing with electronic-scanning antennas) . Of course, the antennas inquestion may be array antennas composed of a large number of horns (orof any other type of antenna: dipoles, patches, etc.) and waveguides maybe formed in layers of the structure, as close as possible to theantennas.

The other layers of the structure 11 can comprise complex electroniccircuits: arrays of phase shifters, transmission/reception circuits,power supply, etc. or else they may be stiffening layers or layers inwhich electromechanical or optical elements are integrated. Of course,if electrical connections need to be provided between circuits ofdifferent layers, these connections are made in a manner similar to thatused to connect together circuits belonging to different faces or layersof a simple or multi-layer conventional structure of printed circuits.

The various layers of the structure of the invention may be assembledtogether by any appropriate means: welding, adhesive bonding, mechanicalclamping, etc. This structure may either be housed inside an existingcasing, or constitute this casing via its outer layers, these outerlayers and the lateral faces of the other layers being machined and/orcovered with an appropriate material so as to constitute the casing,which may easily be profiled to ensure aerodynamic continuity with thesurrounding surfaces (external surfaces of the aerofoils and the like,of the “pods”, etc. in the case of an aircraft) and to ensure thenecessary leaktightness, as the case may be.

Represented in FIG. 6, in a very simplified manner, is an exemplaryvolume 19 with a more complex shape than the volume described above.This volume 19 comprises a first volume portion 20, similar to theportion 8 of FIG. 2, and another volume 21 forming an appendage on oneof the substantially plane faces of the volume 20. This appendage 21also has, in cross section, a “U” profile whose branches are, forexample, perpendicular to that surface of the volume 20 on which thisappendage is formed. The strata of the multi-layer structure 22 occupyonly the volume 20 and are parallel to its plane surfaces, whilst thevolume 21 is occupied by a multi-layer structure 23, the surfaces ofwhose layers are perpendicular to those of the layers of the structure22. Diagrammatically represented at 24 are connections made directly, inan appropriate manner, between the circuits of the structure 22 andthose of the structure 23.

The structure in accordance with the invention allows not only optimaluse to be made of restricted volumes, and/or of complex shapes, but alsomakes it possible to incorporate therein the maximum possible number ofelements by using integration techniques known per se, and thereby toreduce the length and/or the number of connection lines between thevarious elements, and therefore, as the case may be, to improve theirperformance by virtue of this maximum integration, this structurepossibly even being a constituent element of the carrier.

What is claimed is:
 1. A structure of electronic circuits having aphysical form optimized to conform to a volume available within ahousing having a frontal shape with a small radius of curvature andhaving at least one plane surface, the structure comprising: a stack ofplane layers including at least one electronic circuit and configured tobe placed in the housing and to border the at least one plane surface;wherein the plane layers are parallel to the plane surface; and whereina front edge of the plane layers closely conforms to the frontal shapeof the housing with the small radius of curvature.
 2. The structure ofclaim 1, wherein: the stack of plane layers includes at least oneelement from a group of elements including: electrical circuits, opticalcircuits, waveguides, discrete components, integrated components,insulation elements, thermal elements, stiffening elements, andprotector elements; and the layers in the stack of plane layers aresubstantially parallel to a largest plane surface of the housing.
 3. Thestructure of claim 2, wherein the elements are included or formed inseveral successive layers.
 4. The structure of claim 1, wherein theplane layers have thicknesses of different respective values.
 5. Thestructure of claim 1, wherein: the structure is configured to be housedin a volume having several planar surfaces with mutually differentorientations, and the structure comprises several different stacks oflayers respectively parallel to the planar surfaces.
 6. The structure ofclaim 1, wherein the structure is configured as part of an airborneradar.
 7. The structure of claim 1, wherein the structure is configuredas part of electronic warfare hardware.
 8. The structure of claim 1,wherein the structure is configured as part of telecommunicationshardware.